linux/fs/gfs2/sys.c
Steven Whitehouse d564053f07 GFS2: Clean up freeze code
The freeze code has not been looked at a lot recently. Upstream has
moved on, and this is an attempt to catch us back up again. There
is a vfs level interface for the freeze code which can be called
from our (obsolete, but kept for backward compatibility purposes)
sysfs freeze interface. This means freezing this way vs. doing it
from the ioctl should now work in identical fashion.

As a result of this, the freeze function is only called once
and we can drop our own special purpose code for counting the
number of freezes.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
2013-01-29 10:29:05 +00:00

678 lines
17 KiB
C

/*
* Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
* Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU General Public License version 2.
*/
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/completion.h>
#include <linux/buffer_head.h>
#include <linux/module.h>
#include <linux/kobject.h>
#include <asm/uaccess.h>
#include <linux/gfs2_ondisk.h>
#include <linux/genhd.h>
#include "gfs2.h"
#include "incore.h"
#include "sys.h"
#include "super.h"
#include "glock.h"
#include "quota.h"
#include "util.h"
#include "glops.h"
#include "recovery.h"
struct gfs2_attr {
struct attribute attr;
ssize_t (*show)(struct gfs2_sbd *, char *);
ssize_t (*store)(struct gfs2_sbd *, const char *, size_t);
};
static ssize_t gfs2_attr_show(struct kobject *kobj, struct attribute *attr,
char *buf)
{
struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
return a->show ? a->show(sdp, buf) : 0;
}
static ssize_t gfs2_attr_store(struct kobject *kobj, struct attribute *attr,
const char *buf, size_t len)
{
struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
struct gfs2_attr *a = container_of(attr, struct gfs2_attr, attr);
return a->store ? a->store(sdp, buf, len) : len;
}
static const struct sysfs_ops gfs2_attr_ops = {
.show = gfs2_attr_show,
.store = gfs2_attr_store,
};
static struct kset *gfs2_kset;
static ssize_t id_show(struct gfs2_sbd *sdp, char *buf)
{
return snprintf(buf, PAGE_SIZE, "%u:%u\n",
MAJOR(sdp->sd_vfs->s_dev), MINOR(sdp->sd_vfs->s_dev));
}
static ssize_t fsname_show(struct gfs2_sbd *sdp, char *buf)
{
return snprintf(buf, PAGE_SIZE, "%s\n", sdp->sd_fsname);
}
static int gfs2_uuid_valid(const u8 *uuid)
{
int i;
for (i = 0; i < 16; i++) {
if (uuid[i])
return 1;
}
return 0;
}
static ssize_t uuid_show(struct gfs2_sbd *sdp, char *buf)
{
struct super_block *s = sdp->sd_vfs;
const u8 *uuid = s->s_uuid;
buf[0] = '\0';
if (!gfs2_uuid_valid(uuid))
return 0;
return snprintf(buf, PAGE_SIZE, "%pUB\n", uuid);
}
static ssize_t freeze_show(struct gfs2_sbd *sdp, char *buf)
{
struct super_block *sb = sdp->sd_vfs;
int frozen = (sb->s_writers.frozen == SB_UNFROZEN) ? 0 : 1;
return snprintf(buf, PAGE_SIZE, "%u\n", frozen);
}
static ssize_t freeze_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
{
int error;
int n = simple_strtol(buf, NULL, 0);
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
switch (n) {
case 0:
error = thaw_super(sdp->sd_vfs);
break;
case 1:
error = freeze_super(sdp->sd_vfs);
break;
default:
return -EINVAL;
}
if (error) {
fs_warn(sdp, "freeze %d error %d", n, error);
return error;
}
return len;
}
static ssize_t withdraw_show(struct gfs2_sbd *sdp, char *buf)
{
unsigned int b = test_bit(SDF_SHUTDOWN, &sdp->sd_flags);
return snprintf(buf, PAGE_SIZE, "%u\n", b);
}
static ssize_t withdraw_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
{
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (simple_strtol(buf, NULL, 0) != 1)
return -EINVAL;
gfs2_lm_withdraw(sdp,
"GFS2: fsid=%s: withdrawing from cluster at user's request\n",
sdp->sd_fsname);
return len;
}
static ssize_t statfs_sync_store(struct gfs2_sbd *sdp, const char *buf,
size_t len)
{
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (simple_strtol(buf, NULL, 0) != 1)
return -EINVAL;
gfs2_statfs_sync(sdp->sd_vfs, 0);
return len;
}
static ssize_t quota_sync_store(struct gfs2_sbd *sdp, const char *buf,
size_t len)
{
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (simple_strtol(buf, NULL, 0) != 1)
return -EINVAL;
gfs2_quota_sync(sdp->sd_vfs, 0);
return len;
}
static ssize_t quota_refresh_user_store(struct gfs2_sbd *sdp, const char *buf,
size_t len)
{
int error;
u32 id;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
id = simple_strtoul(buf, NULL, 0);
error = gfs2_quota_refresh(sdp, 1, id);
return error ? error : len;
}
static ssize_t quota_refresh_group_store(struct gfs2_sbd *sdp, const char *buf,
size_t len)
{
int error;
u32 id;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
id = simple_strtoul(buf, NULL, 0);
error = gfs2_quota_refresh(sdp, 0, id);
return error ? error : len;
}
static ssize_t demote_rq_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
{
struct gfs2_glock *gl;
const struct gfs2_glock_operations *glops;
unsigned int glmode;
unsigned int gltype;
unsigned long long glnum;
char mode[16];
int rv;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
rv = sscanf(buf, "%u:%llu %15s", &gltype, &glnum,
mode);
if (rv != 3)
return -EINVAL;
if (strcmp(mode, "EX") == 0)
glmode = LM_ST_UNLOCKED;
else if ((strcmp(mode, "CW") == 0) || (strcmp(mode, "DF") == 0))
glmode = LM_ST_DEFERRED;
else if ((strcmp(mode, "PR") == 0) || (strcmp(mode, "SH") == 0))
glmode = LM_ST_SHARED;
else
return -EINVAL;
if (gltype > LM_TYPE_JOURNAL)
return -EINVAL;
if (gltype == LM_TYPE_NONDISK && glnum == GFS2_TRANS_LOCK)
glops = &gfs2_trans_glops;
else
glops = gfs2_glops_list[gltype];
if (glops == NULL)
return -EINVAL;
if (!test_and_set_bit(SDF_DEMOTE, &sdp->sd_flags))
fs_info(sdp, "demote interface used\n");
rv = gfs2_glock_get(sdp, glnum, glops, 0, &gl);
if (rv)
return rv;
gfs2_glock_cb(gl, glmode);
gfs2_glock_put(gl);
return len;
}
#define GFS2_ATTR(name, mode, show, store) \
static struct gfs2_attr gfs2_attr_##name = __ATTR(name, mode, show, store)
GFS2_ATTR(id, 0444, id_show, NULL);
GFS2_ATTR(fsname, 0444, fsname_show, NULL);
GFS2_ATTR(uuid, 0444, uuid_show, NULL);
GFS2_ATTR(freeze, 0644, freeze_show, freeze_store);
GFS2_ATTR(withdraw, 0644, withdraw_show, withdraw_store);
GFS2_ATTR(statfs_sync, 0200, NULL, statfs_sync_store);
GFS2_ATTR(quota_sync, 0200, NULL, quota_sync_store);
GFS2_ATTR(quota_refresh_user, 0200, NULL, quota_refresh_user_store);
GFS2_ATTR(quota_refresh_group, 0200, NULL, quota_refresh_group_store);
GFS2_ATTR(demote_rq, 0200, NULL, demote_rq_store);
static struct attribute *gfs2_attrs[] = {
&gfs2_attr_id.attr,
&gfs2_attr_fsname.attr,
&gfs2_attr_uuid.attr,
&gfs2_attr_freeze.attr,
&gfs2_attr_withdraw.attr,
&gfs2_attr_statfs_sync.attr,
&gfs2_attr_quota_sync.attr,
&gfs2_attr_quota_refresh_user.attr,
&gfs2_attr_quota_refresh_group.attr,
&gfs2_attr_demote_rq.attr,
NULL,
};
static void gfs2_sbd_release(struct kobject *kobj)
{
struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
kfree(sdp);
}
static struct kobj_type gfs2_ktype = {
.release = gfs2_sbd_release,
.default_attrs = gfs2_attrs,
.sysfs_ops = &gfs2_attr_ops,
};
/*
* lock_module. Originally from lock_dlm
*/
static ssize_t proto_name_show(struct gfs2_sbd *sdp, char *buf)
{
const struct lm_lockops *ops = sdp->sd_lockstruct.ls_ops;
return sprintf(buf, "%s\n", ops->lm_proto_name);
}
static ssize_t block_show(struct gfs2_sbd *sdp, char *buf)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
ssize_t ret;
int val = 0;
if (test_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags))
val = 1;
ret = sprintf(buf, "%d\n", val);
return ret;
}
static ssize_t block_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
ssize_t ret = len;
int val;
val = simple_strtol(buf, NULL, 0);
if (val == 1)
set_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
else if (val == 0) {
clear_bit(DFL_BLOCK_LOCKS, &ls->ls_recover_flags);
smp_mb__after_clear_bit();
gfs2_glock_thaw(sdp);
} else {
ret = -EINVAL;
}
return ret;
}
static ssize_t lkfirst_show(struct gfs2_sbd *sdp, char *buf)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
return sprintf(buf, "%d\n", ls->ls_first);
}
static ssize_t lkfirst_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
{
unsigned first;
int rv;
rv = sscanf(buf, "%u", &first);
if (rv != 1 || first > 1)
return -EINVAL;
rv = wait_for_completion_killable(&sdp->sd_locking_init);
if (rv)
return rv;
spin_lock(&sdp->sd_jindex_spin);
rv = -EBUSY;
if (test_bit(SDF_NOJOURNALID, &sdp->sd_flags) == 0)
goto out;
rv = -EINVAL;
if (sdp->sd_args.ar_spectator)
goto out;
if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
goto out;
sdp->sd_lockstruct.ls_first = first;
rv = 0;
out:
spin_unlock(&sdp->sd_jindex_spin);
return rv ? rv : len;
}
static ssize_t first_done_show(struct gfs2_sbd *sdp, char *buf)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
return sprintf(buf, "%d\n", !!test_bit(DFL_FIRST_MOUNT_DONE, &ls->ls_recover_flags));
}
int gfs2_recover_set(struct gfs2_sbd *sdp, unsigned jid)
{
struct gfs2_jdesc *jd;
int rv;
spin_lock(&sdp->sd_jindex_spin);
rv = -EBUSY;
if (sdp->sd_jdesc->jd_jid == jid)
goto out;
rv = -ENOENT;
list_for_each_entry(jd, &sdp->sd_jindex_list, jd_list) {
if (jd->jd_jid != jid)
continue;
rv = gfs2_recover_journal(jd, false);
break;
}
out:
spin_unlock(&sdp->sd_jindex_spin);
return rv;
}
static ssize_t recover_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
{
unsigned jid;
int rv;
rv = sscanf(buf, "%u", &jid);
if (rv != 1)
return -EINVAL;
if (test_bit(SDF_NORECOVERY, &sdp->sd_flags)) {
rv = -ESHUTDOWN;
goto out;
}
rv = gfs2_recover_set(sdp, jid);
out:
return rv ? rv : len;
}
static ssize_t recover_done_show(struct gfs2_sbd *sdp, char *buf)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
return sprintf(buf, "%d\n", ls->ls_recover_jid_done);
}
static ssize_t recover_status_show(struct gfs2_sbd *sdp, char *buf)
{
struct lm_lockstruct *ls = &sdp->sd_lockstruct;
return sprintf(buf, "%d\n", ls->ls_recover_jid_status);
}
static ssize_t jid_show(struct gfs2_sbd *sdp, char *buf)
{
return sprintf(buf, "%d\n", sdp->sd_lockstruct.ls_jid);
}
static ssize_t jid_store(struct gfs2_sbd *sdp, const char *buf, size_t len)
{
int jid;
int rv;
rv = sscanf(buf, "%d", &jid);
if (rv != 1)
return -EINVAL;
rv = wait_for_completion_killable(&sdp->sd_locking_init);
if (rv)
return rv;
spin_lock(&sdp->sd_jindex_spin);
rv = -EINVAL;
if (sdp->sd_lockstruct.ls_ops->lm_mount == NULL)
goto out;
rv = -EBUSY;
if (test_bit(SDF_NOJOURNALID, &sdp->sd_flags) == 0)
goto out;
rv = 0;
if (sdp->sd_args.ar_spectator && jid > 0)
rv = jid = -EINVAL;
sdp->sd_lockstruct.ls_jid = jid;
clear_bit(SDF_NOJOURNALID, &sdp->sd_flags);
smp_mb__after_clear_bit();
wake_up_bit(&sdp->sd_flags, SDF_NOJOURNALID);
out:
spin_unlock(&sdp->sd_jindex_spin);
return rv ? rv : len;
}
#define GDLM_ATTR(_name,_mode,_show,_store) \
static struct gfs2_attr gdlm_attr_##_name = __ATTR(_name,_mode,_show,_store)
GDLM_ATTR(proto_name, 0444, proto_name_show, NULL);
GDLM_ATTR(block, 0644, block_show, block_store);
GDLM_ATTR(withdraw, 0644, withdraw_show, withdraw_store);
GDLM_ATTR(jid, 0644, jid_show, jid_store);
GDLM_ATTR(first, 0644, lkfirst_show, lkfirst_store);
GDLM_ATTR(first_done, 0444, first_done_show, NULL);
GDLM_ATTR(recover, 0600, NULL, recover_store);
GDLM_ATTR(recover_done, 0444, recover_done_show, NULL);
GDLM_ATTR(recover_status, 0444, recover_status_show, NULL);
static struct attribute *lock_module_attrs[] = {
&gdlm_attr_proto_name.attr,
&gdlm_attr_block.attr,
&gdlm_attr_withdraw.attr,
&gdlm_attr_jid.attr,
&gdlm_attr_first.attr,
&gdlm_attr_first_done.attr,
&gdlm_attr_recover.attr,
&gdlm_attr_recover_done.attr,
&gdlm_attr_recover_status.attr,
NULL,
};
/*
* get and set struct gfs2_tune fields
*/
static ssize_t quota_scale_show(struct gfs2_sbd *sdp, char *buf)
{
return snprintf(buf, PAGE_SIZE, "%u %u\n",
sdp->sd_tune.gt_quota_scale_num,
sdp->sd_tune.gt_quota_scale_den);
}
static ssize_t quota_scale_store(struct gfs2_sbd *sdp, const char *buf,
size_t len)
{
struct gfs2_tune *gt = &sdp->sd_tune;
unsigned int x, y;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
if (sscanf(buf, "%u %u", &x, &y) != 2 || !y)
return -EINVAL;
spin_lock(&gt->gt_spin);
gt->gt_quota_scale_num = x;
gt->gt_quota_scale_den = y;
spin_unlock(&gt->gt_spin);
return len;
}
static ssize_t tune_set(struct gfs2_sbd *sdp, unsigned int *field,
int check_zero, const char *buf, size_t len)
{
struct gfs2_tune *gt = &sdp->sd_tune;
unsigned int x;
if (!capable(CAP_SYS_ADMIN))
return -EACCES;
x = simple_strtoul(buf, NULL, 0);
if (check_zero && !x)
return -EINVAL;
spin_lock(&gt->gt_spin);
*field = x;
spin_unlock(&gt->gt_spin);
return len;
}
#define TUNE_ATTR_3(name, show, store) \
static struct gfs2_attr tune_attr_##name = __ATTR(name, 0644, show, store)
#define TUNE_ATTR_2(name, store) \
static ssize_t name##_show(struct gfs2_sbd *sdp, char *buf) \
{ \
return snprintf(buf, PAGE_SIZE, "%u\n", sdp->sd_tune.gt_##name); \
} \
TUNE_ATTR_3(name, name##_show, store)
#define TUNE_ATTR(name, check_zero) \
static ssize_t name##_store(struct gfs2_sbd *sdp, const char *buf, size_t len)\
{ \
return tune_set(sdp, &sdp->sd_tune.gt_##name, check_zero, buf, len); \
} \
TUNE_ATTR_2(name, name##_store)
TUNE_ATTR(quota_warn_period, 0);
TUNE_ATTR(quota_quantum, 0);
TUNE_ATTR(max_readahead, 0);
TUNE_ATTR(complain_secs, 0);
TUNE_ATTR(statfs_slow, 0);
TUNE_ATTR(new_files_jdata, 0);
TUNE_ATTR(quota_simul_sync, 1);
TUNE_ATTR(statfs_quantum, 1);
TUNE_ATTR_3(quota_scale, quota_scale_show, quota_scale_store);
static struct attribute *tune_attrs[] = {
&tune_attr_quota_warn_period.attr,
&tune_attr_quota_quantum.attr,
&tune_attr_max_readahead.attr,
&tune_attr_complain_secs.attr,
&tune_attr_statfs_slow.attr,
&tune_attr_quota_simul_sync.attr,
&tune_attr_statfs_quantum.attr,
&tune_attr_quota_scale.attr,
&tune_attr_new_files_jdata.attr,
NULL,
};
static struct attribute_group tune_group = {
.name = "tune",
.attrs = tune_attrs,
};
static struct attribute_group lock_module_group = {
.name = "lock_module",
.attrs = lock_module_attrs,
};
int gfs2_sys_fs_add(struct gfs2_sbd *sdp)
{
struct super_block *sb = sdp->sd_vfs;
int error;
char ro[20];
char spectator[20];
char *envp[] = { ro, spectator, NULL };
int sysfs_frees_sdp = 0;
sprintf(ro, "RDONLY=%d", (sb->s_flags & MS_RDONLY) ? 1 : 0);
sprintf(spectator, "SPECTATOR=%d", sdp->sd_args.ar_spectator ? 1 : 0);
sdp->sd_kobj.kset = gfs2_kset;
error = kobject_init_and_add(&sdp->sd_kobj, &gfs2_ktype, NULL,
"%s", sdp->sd_table_name);
if (error)
goto fail_reg;
sysfs_frees_sdp = 1; /* Freeing sdp is now done by sysfs calling
function gfs2_sbd_release. */
error = sysfs_create_group(&sdp->sd_kobj, &tune_group);
if (error)
goto fail_reg;
error = sysfs_create_group(&sdp->sd_kobj, &lock_module_group);
if (error)
goto fail_tune;
error = sysfs_create_link(&sdp->sd_kobj,
&disk_to_dev(sb->s_bdev->bd_disk)->kobj,
"device");
if (error)
goto fail_lock_module;
kobject_uevent_env(&sdp->sd_kobj, KOBJ_ADD, envp);
return 0;
fail_lock_module:
sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
fail_tune:
sysfs_remove_group(&sdp->sd_kobj, &tune_group);
fail_reg:
free_percpu(sdp->sd_lkstats);
fs_err(sdp, "error %d adding sysfs files", error);
if (sysfs_frees_sdp)
kobject_put(&sdp->sd_kobj);
else
kfree(sdp);
sb->s_fs_info = NULL;
return error;
}
void gfs2_sys_fs_del(struct gfs2_sbd *sdp)
{
sysfs_remove_link(&sdp->sd_kobj, "device");
sysfs_remove_group(&sdp->sd_kobj, &tune_group);
sysfs_remove_group(&sdp->sd_kobj, &lock_module_group);
kobject_put(&sdp->sd_kobj);
}
static int gfs2_uevent(struct kset *kset, struct kobject *kobj,
struct kobj_uevent_env *env)
{
struct gfs2_sbd *sdp = container_of(kobj, struct gfs2_sbd, sd_kobj);
struct super_block *s = sdp->sd_vfs;
const u8 *uuid = s->s_uuid;
add_uevent_var(env, "LOCKTABLE=%s", sdp->sd_table_name);
add_uevent_var(env, "LOCKPROTO=%s", sdp->sd_proto_name);
if (!test_bit(SDF_NOJOURNALID, &sdp->sd_flags))
add_uevent_var(env, "JOURNALID=%d", sdp->sd_lockstruct.ls_jid);
if (gfs2_uuid_valid(uuid))
add_uevent_var(env, "UUID=%pUB", uuid);
return 0;
}
static const struct kset_uevent_ops gfs2_uevent_ops = {
.uevent = gfs2_uevent,
};
int gfs2_sys_init(void)
{
gfs2_kset = kset_create_and_add("gfs2", &gfs2_uevent_ops, fs_kobj);
if (!gfs2_kset)
return -ENOMEM;
return 0;
}
void gfs2_sys_uninit(void)
{
kset_unregister(gfs2_kset);
}